Cancer is a group of diseases involving abnormal cell growth with the potential to invade or spread to other parts of the body. Cancer generally manifests into abnormal growths of tissue in the form of a tumor that may be localized to a particular area of a patient's body (e.g., associated with a specific body part or organ) or may be spread throughout. Tumors, both benign and malignant, are commonly treated and removed via surgical intervention, as surgery often offers the greatest chance for complete removal and cure, especially if the cancer has not spread to other parts of the body. However, in some instances, surgery alone is insufficient to adequately remove all cancerous tissue from a local environment.
Some procedures are meant to ablate the marginal tissue and any cancerous cells. For example, surgical removal of a breast tumor (e.g., a lumpectomy) may be accompanied by irradiation. Unlike a mastectomy, a lumpectomy removes only the tumor and a small rim (area) of the normal tissue around it. Radiation therapy is provided in an attempt to kill any cancer cells that may remain. Unfortunately, radiation techniques can be costly, require multiple treatments over several months, and can have devastating side effects on a patient's quality of life. Furthermore, radiation may leave some viable cancer cells in the patient.